In article ,
"NY" writes:
We're thinking of getting a Hive remote-controlled central heating
controller/thermostat so we can set our heating to come on several hours
before we get home from holiday etc.

I'm trying to work out whether we need a single- or dual-channel controller.
Hive's customer support was di they wouldn't offer any advice and just
said "speak to a qualified central heating installer". Imagine not being
able to offer any pre-sales advice!

We have a combi boiler which currently has a dual-timer: one for the central
heating and one for the hot water. The hot water is pre-heated in a
reservoir in the boiler, hence the reason for being able to time when that
pre-heat comes on and off, so it's not wasting fuel keeping the reservoir
hot overnight.

Hive say "single-channel for combi; dual channel for conventional boiler
with hot water cylinder". Our system sounds as if it has some features of
both: it's mostly heat-on-demand but with timed pre-heat of a small
reservoir in the boiler.

So, single or dual?

Single, and turn off the hot water pre-heat whilst you are away,
or turn off the hot water heating entirely is that's possible.

Only reason for dual would be if you have multiple heating zones,
or to heat a hot water storage cyclider.

Actually, what you want is to leave the heating on 24x7 whilst you
are away, setback to frost protection. It depends where the stat is,
but 10C is probably the lowest you can go and some insurance companies
require 15C. If you have frost stats physically located in all the
vulnerable places, you can risk lower.
I would assume Hive can do this, but I'm not familar with its capability.

--
Andrew Gabriel
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